In fabricating semiconductor devices, a trade-off typically exists between low leakage current and high drive current. Semiconductive materials exhibiting a high band gap normally provide a low leakage current, conversely, semiconductive materials exhibiting a low band gap normally provide a relatively high drive current. Elemental silicon exhibits a band gap of about 1.1 electron-volts (eV) which is a relatively low band gap providing acceptable drive currents. However, leakage currents can be a problem in certain applications, for example, memory devices. In memory devices, frequent refreshing may be used to address the leakage currents associated with elemental silicon as the semiconductive material in such devices.
In an attempt to reduce the refresh frequency in memory devices, it may be desirable to use alternative semiconductive materials that exhibit a higher band gap than elemental silicon. However, caution may be exercised to avoid integration problems of introducing a different semiconductive material. A different semiconductive material might result in significant processing changes and/or integrated circuit design changes to accommodate the different electronic properties and/or chemical interactions with other materials in the devices. Other apparatuses, in addition to memory devices, may potentially benefit from lessons learned when incorporating higher band gap semiconductive material into memory devices.